A cordless telephone exists which allows the user to come to the door, to ask "who is it" when the door bell is ringing while he is talking on the telephone. Conventional cordless telephones ;f this kind are intended to be portable, thus allowing the user to talk to his companion while moving around. Most of these are of the wireless portable (or handy transceiver) type in which the transmitter and the receiver are housed in a box or handset and an antenna projects from the handset. However, there exists no telephone similar to that of the present invention, which is of the floor or table-to; type and which allows the user to talk with his companion, leaving his hands free.
There exist portable wireless telephones which house a speaker in a box to make the received voice loud, but they are usually of the press talk type. A hands-free telephone that allows transmitting and receiving communications to be made at the same time and that can be conveniently used for various meetings has not yet been realized.
Hands-free wire (or cord) telephones of various kinds have been produced. These telephones house a speaker and a microphone in a box, making it easy to use as an interphone.
With these telephones, however, the voice received through the speaker, which is adjacent to or near the microphone (or separated from the microphone by about 10 cm), is received more strongly by the microphone than the voice of the person who is remote (50 cm or more) from the microphone. As a result, the voice received through the speaker i: fed back through the telephone circuit, causing howling and echo, thereby disturbing the talking through the telephone. To solve this problem, an alternately-talking system actuated by a voice control switch which causes the received voice to vanish at its start and end, or alternatively an echo canceller system (high in cost) is required.